Xu H, Gao Y, Liu Z, Bei Y. Theoretical Investigation of the Hydrolytic Mechanism of α-Functionalized Alkoxysilanes as Effective Crosslinkers and the Difficulty of Deep Vulcanization in RTV Silicone Rubber.
MATERIALS (BASEL, SWITZERLAND) 2018;
11:ma11091526. [PMID:
30149562 PMCID:
PMC6163510 DOI:
10.3390/ma11091526]
[Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Revised: 08/22/2018] [Accepted: 08/22/2018] [Indexed: 06/08/2023]
Abstract
The reactions between α-, γ-ethylenediaminemethyl trimethyl-ketoxime silane (α-, γ-EAMOS) and H₂O were investigated on the geometries of stationary points, the reaction pathway (IRC), thermodynamic and kinetic analysis by density functional theory (DFT) at the B3LYP/6-311G (d, p) level. Interestingly, the results showed that the hydrolysis activity of α-EAMOS is higher than that of γ-EAMOS, due to the influence of an amino substituent in position α-C on silicon. α-EAMOS can be used as a superior crosslinker for room temperature vulcanized (RTV) silicone rubber to achieve rapid crosslinking without a toxic catalyst. Besides, compared with the reaction between α-EAMOS and H₂O, the reactivity between α-EAMOS and hydroxy siloxane (HO⁻Si(CH₃)₂⁻OSiH₃) was discussed. Particularly, it revealed that the deep vulcanization of RTV silicone rubber is difficult.
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